The present invention relates to a device for conveying objects comprising a large numbers of rods, each having ends, the adjacent rods being mutually connected at their ends by connection elements.
In most known devices the rods extend with their ends beyond the connection elements, and said ends are usually provided with loose heads welded to the ends. Said loose heads, and in particular the welds which may be undesirable projections, are unwanted because of wear and tear and damages. In particular when such devices travel around drums, the drum may be damaged. Although solutions to these problems have been suggested, for instance the use of connection elements made of synthetic material instead of metal connection elements, these solutions lead to expensive and complex constructions There Is a need therefore for a device having rods and connection elements, which device has a cheap and a simple construction and which in a suitable manner also prevents the wear and tear caused by the ends of the rods.
It is an object of the present invention to provide a device which meets these needs.
To that end the present invention provides a device for conveying objects comprising a large numbers of rods, the device having opposite edges, each rod having a first and a second end, adjacent rods being mutually connected at their ends by connection elements, each connection element being substantially S-shaped in top view and being provided with a first free end which is situated directed to a centre between the first and second end of the rod, with a second free end which is situated directed to an edge concerned of the device, with a first transverse member and a second transverse member, with a first connection member which connects the first free end to the first transverse member, with a second connection member which connects the first transverse member to the second transverse member, and with a third connection member which connects the second transverse member to the second free end, the second free end of the connection element being situated at a distance from the second connection member, the first connection member of the connection element being provided with a first opening through which the one of the adjacent rods extends and with a second opening through which the other of the adjacent rods extends, the second connection member of the connection element being provided with a third opening through which the one of the adjacent rods extends over a distance and with a fourth opening through which the other of the adjacent rods extends, and the connection element being secured to the one of the adjacent rods near the first free end of the connection element. Such a device with S-shaped connection elements offers a cheap, simple and reliable construction, the ends of the rods lying within the S-shaped connection element, and not extending beyond the third connection member.
The distance over which the rod extends beyond the second connection member is of course chosen such that the rod, when the device is used, cannot come loose from the third opening. In a preferred embodiment of a device according to the present invention the distance is such that the rod concerned extends until in abutment with the third connection member. As a result a more stable construction is obtained.
Although the place of securing mentioned above suffices for the attachment of the rod concerned to the connection element concerned, in a preferred embodiment of a device according to the present invention the rod concerned is secured at a further location to the second transverse member of the connection element. Alternatively or additionally the rod concerned can be secured to the third connection member of the connection element at (yet) a further location.
When the third connection member has a bent shape, so that the second free end is situated further away from the edge of the device than the rest of the third connection member, the edges of the device, in particular the second free ends of the connection elements, In all cases do not form unwanted projections which could cause possible damage to the drums.
In a preferred embodiment of a device according to the present invention for conveying objects along a track, in which the track may have a curve up to a certain radius, the third connection member has a pre-determined length, which determines the certain radius. When travelling a curve of a minimal radius, at an edge of the device the second free end of the connection element will abut the second transverse member of an adjacent connection element, the distance between the adjacent rods being minimal here. At the other edge of the device the distance between the adjacent rods is maximal. The difference in distances between the rods near the opposite edges, which difference determines the minimal radius of a curve to be travelled, therefore is determined by the length of the third connection member.
In order to reduce wear and tear of the second transverse member as a result of friction with the rod concerned, the second transverse member is provided with a groove for at least partially accommodating the rod concerned. Said groove may be a recess which is arranged in the second transverse member, for instance by means of punching, but additionally may for instance be formed by making the second transverse member V-shaped.
The rods and the connection elements may be made of metal and be secured to each other by means of welding, or a press fit of the rod into one or more of the above-mentioned first and third openings.
Alternatively, the rods and the connection elements may be made of a synthetic material and be secured to each other by means of heat welding, adhesive or a press fit of the rod into one or more of the above-mentioned first and third openings.